US 12,088,236 B2
Control of an induction generator of a wind turbine
Miguel Ángel Sepúlveda Gonzalez, Madrid (ES); and Mikel Tapia Pascal, Navarra (ES)
Assigned to Siemens Gamesa Renewable Energy Innovation & Technology S.L., Sarriguren (ES)
Appl. No. 17/800,586
Filed by Siemens Gamesa Renewable Energy Innovation & Technology S.L., Sarriguren (ES)
PCT Filed Feb. 25, 2021, PCT No. PCT/EP2021/054731
§ 371(c)(1), (2) Date Aug. 18, 2022,
PCT Pub. No. WO2021/170743, PCT Pub. Date Sep. 2, 2021.
Claims priority of application No. 20380010 (EP), filed on Feb. 26, 2020.
Prior Publication US 2023/0079096 A1, Mar. 16, 2023
Int. Cl. H02P 9/10 (2006.01); H02P 23/08 (2006.01)
CPC H02P 9/107 (2013.01) [H02P 23/08 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method of controlling an induction generator connected to a utility grid, the method comprising:
receiving an actual grid frequency; and
controlling rotor windings of the generator by a rotor control signal having a rotor winding reference frequency (Ω_ref) being set in dependence of the actual grid frequency;
wherein the rotor winding reference frequency (Ω_ref) is set such that a slip (s) adheres to a predefined value and substantially does not change with changing actual grid frequency (f) at least in a predefined frequency range of the actual grid frequency,
wherein the slip (s) is given by:
s=(Ω(f)−ns(f))/ns(f),
wherein:
f is the actual grid frequency,
Ω is the actual speed of generator at the actual grid frequency f,
ns(f) is a synchronous speed at the actual grid frequency f,
wherein ns in rpm is given by ns=60*f/p, wherein p is the number of pole pairs of the generator rotor and f is given in Hz.